<p>Despite the growing body of research on the digital divide among older adults, three main limitations remain: (a) the lack of studies examining the influence of the digital divide on successful aging; (b) insufficient attention to the interconnections and chain effects among the three levels of the digital divide; and (c) limited research on the role of structural inequalities in the digital divide, particularly in developing countries. Drawing on five-wave nationally representative data from the China Health and Retirement Longitudinal Study (CHARLS) and guided by the three-level digital divide framework and the Diffusion of Innovations theory, this study examined how the digital divide relates to successful aging disparities among Chinese older adults. Our findings revealed a chain effect among three digital divides: early internet adopters demonstrated greater diversity in both device and function diversity, which in turn significantly predicted higher levels of successful aging. Conversely, digital laggards exhibit limited engagement and substantially lower successful aging outcomes. Furthermore, Blinder-Oaxaca decomposition analysis showed that the successful aging divide was partially explained by demographic disparities, particularly that males, urban residents, and those with higher educational attainment have greater internet access. Unequal returns to digital engagement were also observed, with women and more educated individuals gaining greater benefits. These findings underscored the significance of the first-level digital divide: although it reproduced structural inequalities, it simultaneously created crucial opportunities for challenging inequity. Bridging the digital divide thus goes beyond a technological concern and becomes an essential pathway to fostering healthy, equitable aging.</p>